1. Field of the Invention
The present invention relates to a cutter for cutting bundles of fuel elements, with the cutter having a horizontal tube or rod bundle feed. A portion of the radioactive dust, that is produced when a rod bundle is cut, is picked up by scavenging air and is withdrawn with the latter via the chute for the cut-off rod pieces.
2. Description of the Prior Art
German Offenlegungsschrift No. 26 39 850 Chaze et al of Mar. 17, 1977 discloses a fuel element bundle cutter having a vertical rod bundle feed. With this heretofore known cutter, accumulation of radioactive dust is avoided, and those parts that surround the bundle are cooled. To accomplish this, the magazine in which the rod bundle is disposed is cooled by circulated water and by being rinsed or scavenged with nitrogen, which also picks up the dust particles of the nuclear fuel that are produced when the bundle is cut. Quite apart from the fact that this heretofore known cutter is a so-called vertical bundle cutter, a separate or special withdrawal of cutting dust is not provided.
With a fuel element bundle cutter that has horizontal rod bundle feed, such as is disclosed, for example, in U.S. Pat. No. 4,528,879 Eisenacher dated July 16, 1985, which belongs to the assignee of the present application, the uranium dust that trickles out of the open rods during cutting of the rod bundle is partially picked up by the scavenging air and is conveyed along with the latter through the outlet opening for the cutoff rod pieces in the lower part of the cutter housing into the chute that is connected thereto and that opens into an apparatus for removal of the like. The uranium dust portion that is not picked up by the scavenging air in the lower part of the cutter housing falls through the gap between the housing wall and the cutter carriages, and gradually accumulates on the bottom of the bottom part of the cutter housing. If the ability of the bundle cutter to function is to be maintained, and clogging in the lower part of the cutter housing is to be avoided, this accumulated radioactive dust must be removed after a certain amount of operating time. To remove the accumulated uranium dust from the lower part of the cutter housing, it is first necessary with this type of cutter to dismantle the upper part of the housing and the cutter carriages. Subsequently, while observing safety regulations, the uranium dust is lifted out of the lower part of the housing by means of a spoon-like, remotely controllable manipulator.
It is not advisable to use a liquid to remove the accumulated uranium dust from the fuel element bundle cutter because residual moisture remains in the lower part of the cutter housing and actually enhances accumulation of dust. These types of dust removal are not only very laborious, but are also expensive, because the fuel element bundle cutter cannot be used for a relatively long period of time during the dust removal process.
An object of the present invention therefore is to embody a fuel element bundle cutter of the aforementioned general type that is equipped with withdrawal means for the cutting dust in such a way that the residual radioactive dust is automatically and continuously withdrawn from the cutter housing and is conveyed to the removal mechanism without having to shut the bundle cutter down.